There's some occasional discussion of the different energy from different formulations (brands) and granulations -like Swiss has 10% more energy than the equivalent in Goex, or that FFFG has more energy per volume than FFG.Swiss, as we have read here a number of times before, tends to be at least 10% more energetic than the best US-made powder, whatever that might be.
It seems the manufacturer's don't put their powders head-head in testing like that, and most shooters find a preferred powder, develop a load and stick with that...I suppose if a shooter had samples of each, and the equipment and time, we would have some data to review that could give some expected velocities -something like you'd see in a cartridge reloading manual.